My 3yr old Jack Chi uses a doggy door all day with no problems. The dogs are not allowed upstairs where the bedrooms are but are free to roam the 1st floor which is all tile. Almost every morning when I come downstairs I find a place where my dog has peed inside. The dogs (we also have a chocolate lab) have access to the doggy door all day/night so why isn't he going out the doggy door to pee at night like he does during the day?